=log2 5*log5 81*log3 4+ln√e =log(2)5x 4log(5)3x2log(3)2+1/2lne =8[log(3)5/log(3)2] xlog(5)3xlog(3)2+1/2 =8log(3)5xlog(5)3+1/2 =8+1/2 =8,5.